1. Field of the Invention
The invention relates generally to techniques of estimating significant or meaningful places or regions visited by a user who carries a mobile communication device while traveling.
2. Description of the Related Art
In recent years, it has been popular to incorporate a positioning function such as a GPS (Global Positioning System) into a mobile terminal represented by a mobile phone. In such a situation, a user of such a mobile terminal can measure the user's current position using the mobile terminal, and can transmit the measured position to a server via a network, allowing the user to be provided with various types of location-based services or applications.
A technique is known in which a user's geographical locations are measured at the user's mobile terminal through its GPS, the measured locations are sent from the mobile terminal to a server, the server is operated to calculate geographical regions visited by the user, based on the user's location history represented with the location data, and a service or a set of information tailored to the calculated geographical regions is offered from the server to the user, as disclosed in, for example, Patent Document No. 1 listed below.
This technique allows clustering of the user's locations measured by the user's mobile terminal, based on the distances between the user's locations.
This technique can geographically measure places visited by a mobile-terminal user, but cannot measure or estimate the implications of each place visited (i.e., whether or not each place is significant or meaningful to the user). In this technique, a server can provide the user with a service or a set of information tailored to the place where the user is located, but a desired service or a desired set of information to be provided to the user varies depending on the implication or significance of the user's place (whether the place is significant).
In an example, when the user stays at a particular place for a long time, a desirable service or information to be provided with the user can be completely different between when the place is the user's home and when the place is the user's office. Typically, implications of a place which is visited by a user and is measured using the GPS are measured using information instructed by the user, or using information previously stored in association with the user.
An alternative technique is also known of estimating a user's significant places at the user's mobile terminal, by learning technology, based on a history of the user's locations measured at the user's mobile terminal through its GPS technology, as disclosed in, for example, Non-Patent Document No. 1 listed below. This technique requires measurement of location data using the GPS technology at regular time intervals.
A still alternative technique is also known of estimating a user's significant places using a mixed Gaussian. Mixture Model (distribution), at the user's mobile terminal, by learning technology, based on a history of the user's locations measured at the user's mobile terminal through its GPS, as disclosed in, for example, Non-Patent Document No. 2 listed below.